DEMOSAT

Mission Profile

Inaugural Launch

March 27, 1999 Sea Launch's inaugural launch on March 27, 1999, validated the program concept and demonstrated system capability. This was the culmination of four years of intense development work performed by thousands of aerospace and marine professionals throughout the world. The payload for the first launch was designed to mimic the mass properties of a 4,500 kg commercial spacecraft. The mission injected the satellite into a nominal geostationary transfer orbit with 4,900 kg of equivalent performance, which allowed the perigee to be lofted from 200 to 650 km.

Demonstrating the performance of a standard commercial mission, DemoSat executed a precisely controlled flight profile as one of the most highly instrumented test missions ever flown. More than 130 sensors measured payload environments, validating Sea Launch's ability to safely and accurately deliver the payload to its orbit.

Sensor telemetry data was transmitted in real-time from the payload directly to the command ship during line-of-sight communications, then via TDRSS relay to North American land-based relay stations, and back to the command ship via INTELSAT. A quick-look analysis was performed by team members at the launch site aboard the command ship and by the Seattle-based payload integration and mission analysis team. Over 16 gigabytes of post-flight recorded data were analyzed to fully verify mission performance.

Demonstrating the performance of a standard commercial mission, DemoSat executed a precisely controlled flight profile as one of the most highly instrumented test missions ever flown. More than 130 sensors measured payload environments, validating Sea Launch's ability to safely and accurately deliver the payload to its orbit. Sensor telemetry data was transmitted in real-time from the payload directly to the command ship during line-of-sight communications, then via TDRSS relay to North American land-based relay stations, and back to the command ship via INTELSAT. A quick-look analysis was performed by team members at the launch site aboard the command ship and by the Seattle-based payload integration and mission analysis team. Over 16 gigabytes of post-flight recorded data were analyzed to fully verify mission performance.

The launch window opened at 2:15 p.m. PST, on Saturday, March 27. After a brief delay in initiating the final count-down software, the five-hour terminal count proceeded without interruption. Liftoff occurred 3.9 sec after engine ignition with a gross liftoff weight of 1 million lb and thrust of 1.6 million lb. Maximum dynamic pressure of 5,200 kgf/m2 was experienced 62 sec into flight. First stage separation occurred at 2 min, 26 sec. Fairing separation occurred at 3 min, 20 sec. Third-stage ignition occurred at 204.1 km altitude, completing the transition into the initial injection orbit. For this mission, the third stage performed a second burn for placement into the final transfer orbit. For other missions, specific profiles are designed to maximize performance via tailored staging, burn duration and multiple third stage burns as required.

Analysis results indicated this launch was an outstanding success. Injection accuracy was within 1.27 sigma of the target and environments met all success criteria. The inaugural flight of Sea Launch reflects the efforts of the world's most internationally integrated launch team. Through the harmonized efforts of Boeing, Energia, SDO Yuzhnoye/PO Yuzhmash, and Kvaerner employees, this launch demonstrates the tremendous feats that can be achieved through global cooperation, serving a global market.